ἐν δὲ μηνὸς πρῶτον τύχεν ἆμαρ → it chanced to be on the first of the month, that day fell on the first of the month
-ου, ὁ alejandrino ét. de Alejandría, Eratosth. y Didym. en St.Byz.s.u. Ἀλαξάνδρειαι.